Notify

Notify 2.0.0

Bundle: org.apache.nifi | nifi-standard-nar
Description: Caches a release signal identifier in the distributed cache, optionally along with the FlowFile's attributes. Any flow files held at a corresponding Wait processor will be released once this signal in the cache is discovered.
Tags: cache, distributed, map, notify, release, signal
Input Requirement: REQUIRED
Supports Sensitive Dynamic Properties: false

Properties

Attribute Cache Regex
Any attributes whose names match this regex will be stored in the distributed cache to be copied to any FlowFiles released from a corresponding Wait processor. Note that the uuid attribute will not be cached regardless of this value. If blank, no attributes will be cached.

Display Name

Attribute Cache Regex

Description

Any attributes whose names match this regex will be stored in the distributed cache to be copied to any FlowFiles released from a corresponding Wait processor. Note that the uuid attribute will not be cached regardless of this value. If blank, no attributes will be cached.

API Name

attribute-cache-regex

Expression Language Scope

Not Supported

Sensitive

false

Required

false
Distributed Cache Service
The Controller Service that is used to cache release signals in order to release files queued at a corresponding Wait processor

Display Name

Distributed Cache Service

Description

The Controller Service that is used to cache release signals in order to release files queued at a corresponding Wait processor

API Name

distributed-cache-service

Service Interface

org.apache.nifi.distributed.cache.client.AtomicDistributedMapCacheClient

Service Implementations

org.apache.nifi.hazelcast.services.cacheclient.HazelcastMapCacheClient

org.apache.nifi.distributed.cache.client.MapCacheClientService

org.apache.nifi.redis.service.RedisDistributedMapCacheClientService

Expression Language Scope

Not Supported

Sensitive

false

Required

true
Release Signal Identifier
A value, or the results of an Attribute Expression Language statement, which will be evaluated against a FlowFile in order to determine the release signal cache key

Display Name

Release Signal Identifier

Description

A value, or the results of an Attribute Expression Language statement, which will be evaluated against a FlowFile in order to determine the release signal cache key

API Name

release-signal-id

Expression Language Scope

Environment variables and FlowFile Attributes

Sensitive

false

Required

true
Signal Buffer Count
Specify the maximum number of incoming flow files that can be buffered until signals are notified to cache service. The more buffer can provide the better performance, as it reduces the number of interactions with cache service by grouping signals by signal identifier when multiple incoming flow files share the same signal identifier.

Display Name

Signal Buffer Count

Description

Specify the maximum number of incoming flow files that can be buffered until signals are notified to cache service. The more buffer can provide the better performance, as it reduces the number of interactions with cache service by grouping signals by signal identifier when multiple incoming flow files share the same signal identifier.

API Name

signal-buffer-count

Default Value

1

Expression Language Scope

Not Supported

Sensitive

false

Required

true
Signal Counter Delta
A value, or the results of an Attribute Expression Language statement, which will be evaluated against a FlowFile in order to determine the signal counter delta. Specify how much the counter should increase. For example, if multiple signal events are processed at upstream flow in batch oriented way, the number of events processed can be notified with this property at once. Zero (0) has a special meaning, it clears target count back to 0, which is especially useful when used with Wait Releasable FlowFile Count = Zero (0) mode, to provide 'open-close-gate' type of flow control. One (1) can open a corresponding Wait processor, and Zero (0) can negate it as if closing a gate.

Display Name

Signal Counter Delta

Description

A value, or the results of an Attribute Expression Language statement, which will be evaluated against a FlowFile in order to determine the signal counter delta. Specify how much the counter should increase. For example, if multiple signal events are processed at upstream flow in batch oriented way, the number of events processed can be notified with this property at once. Zero (0) has a special meaning, it clears target count back to 0, which is especially useful when used with Wait Releasable FlowFile Count = Zero (0) mode, to provide 'open-close-gate' type of flow control. One (1) can open a corresponding Wait processor, and Zero (0) can negate it as if closing a gate.

API Name

signal-counter-delta

Default Value

1

Expression Language Scope

Environment variables and FlowFile Attributes

Sensitive

false

Required

true
Signal Counter Name
A value, or the results of an Attribute Expression Language statement, which will be evaluated against a FlowFile in order to determine the signal counter name. Signal counter name is useful when a corresponding Wait processor needs to know the number of occurrences of different types of events, such as success or failure, or destination data source names, etc.

Display Name

Signal Counter Name

Description

A value, or the results of an Attribute Expression Language statement, which will be evaluated against a FlowFile in order to determine the signal counter name. Signal counter name is useful when a corresponding Wait processor needs to know the number of occurrences of different types of events, such as success or failure, or destination data source names, etc.

API Name

signal-counter-name

Default Value

default

Expression Language Scope

Environment variables and FlowFile Attributes

Sensitive

false

Required

true

Relationships

Name	Description
failure	When the cache cannot be reached, or if the Release Signal Identifier evaluates to null or empty, FlowFiles will be routed to this relationship
success	All FlowFiles where the release signal has been successfully entered in the cache will be routed to this relationship

Writes Attributes

Name	Description
notified	All FlowFiles will have an attribute 'notified'. The value of this attribute is true, is the FlowFile is notified, otherwise false.